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Dimidiadinium sphaerocephalis
Dimidiadinium sphaerocephalis (Vozzhennikova, 1967) Brideaux, 1977
Originally Tubotuberella, subsequently Dimidiadinium.
Tax. jr. synonym of Gonyaulacysta eisenackii (Deflandre, 1938) Dodekova, 1967, according to Sarjeant, 1982b.
Questionable tax. sr. synonym of Leptodinium (subsequently Tubotuberella) egemenii Gitmez, 1970 and questionable tax. sr. synonym of Gonyaulacysta (now Tubotuberella) vozzhennikovae Sarjeant, 1982, according to Brenner, 1988, who also listed Tubotuberella sphaerocephalis as a tax. jr. synonym of Tubotuberella (now Gonyaulacysta) eisenackii (Deflandre, 1938) Stover and Evitt, 1978. Because of the uncertainty concerning Brenner"s intentions, Lentin and Williams, 1993, retained Tubotuberella egemenii and Tubotuberella vozzhennikovae as separate species.
Davies, 1983, retained this species in Tubotuberella.
Holotype: Vozzhennikova, 1967, pl.103, fig.2; Lentin and Vozzhennikova, 1990, text-fig.55 (lost, according to Lentin and Vozzhennikova, 1990)
Lectotype: none available, according to Lentin and Vozzhennikova, 1990.
Locus typicus: Moscow region, USSR
Stratum typicum: Late Jurassic
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Lentin and Vozzhennikova, 1967, p.181: Tubotuberella sphaerocephalis
Theca has the shape of an inverted round flask with a short neck. Envelope thin and closely applied to the large, circular or oval internal body which extents a little way into the tubular antapical part of the hypotheca. The latter is constricted just before its extremity where it terminates in a square aperture, the sides of which are somewhat concave and the angles bear small spines. Epitheca hemispherical with a small apical outgrowth which bifurcatel at the distal end. Transverse furrow annulate, its ends widely separated; from them run ribs which delimlt a broad ventral field. Surface of envelope subdivided into fields by longitudinal ribs which run from the transverse furrow to the poles. Ribs toothed with small processes, which may be bifurcated at the ends, on their margins. Similar ornamentation occurs along the margins of the transverse furrow ant ventral fields.
Size: Holotype, lengh 76 Ám, width 59 Ám, width of paracingulum about 4 Ám; endocyst length 49 Ám, width 49 Ám. Range, length 73-79 Ám, width 54-59 Ám.
Originally Tubotuberella, subsequently Dimidiadinium.
Tax. jr. synonym of Gonyaulacysta eisenackii (Deflandre, 1938) Dodekova, 1967, according to Sarjeant, 1982b.
Questionable tax. sr. synonym of Leptodinium (subsequently Tubotuberella) egemenii Gitmez, 1970 and questionable tax. sr. synonym of Gonyaulacysta (now Tubotuberella) vozzhennikovae Sarjeant, 1982, according to Brenner, 1988, who also listed Tubotuberella sphaerocephalis as a tax. jr. synonym of Tubotuberella (now Gonyaulacysta) eisenackii (Deflandre, 1938) Stover and Evitt, 1978. Because of the uncertainty concerning Brenner"s intentions, Lentin and Williams, 1993, retained Tubotuberella egemenii and Tubotuberella vozzhennikovae as separate species.
Davies, 1983, retained this species in Tubotuberella.
Holotype: Vozzhennikova, 1967, pl.103, fig.2; Lentin and Vozzhennikova, 1990, text-fig.55 (lost, according to Lentin and Vozzhennikova, 1990)
Lectotype: none available, according to Lentin and Vozzhennikova, 1990.
Locus typicus: Moscow region, USSR
Stratum typicum: Late Jurassic
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Lentin and Vozzhennikova, 1967, p.181: Tubotuberella sphaerocephalis
Theca has the shape of an inverted round flask with a short neck. Envelope thin and closely applied to the large, circular or oval internal body which extents a little way into the tubular antapical part of the hypotheca. The latter is constricted just before its extremity where it terminates in a square aperture, the sides of which are somewhat concave and the angles bear small spines. Epitheca hemispherical with a small apical outgrowth which bifurcatel at the distal end. Transverse furrow annulate, its ends widely separated; from them run ribs which delimlt a broad ventral field. Surface of envelope subdivided into fields by longitudinal ribs which run from the transverse furrow to the poles. Ribs toothed with small processes, which may be bifurcated at the ends, on their margins. Similar ornamentation occurs along the margins of the transverse furrow ant ventral fields.
Size: Holotype, lengh 76 Ám, width 59 Ám, width of paracingulum about 4 Ám; endocyst length 49 Ám, width 49 Ám. Range, length 73-79 Ám, width 54-59 Ám.